Hi , i have this problem , i need help with this exercise
If b B[a,r] , prove that exist s>0 such that B[a,r] B[b,s] =
Please, please get in the habit of posting the meaning of notations that you use.
If the ordinary ball then the statement is false.
If the ordinary closed ball then the statement is true.
Which is it? Or is it something altogether different?